Association between neuropathology and brain volume in the Framingham Heart Study.

Studies of clinical and community cohorts have shown that antemortem imaging measures of hippocampal volume have correlated with postmortem Alzheimer pathology. Fewer studies have examined the relationship between both Alzheimer and cerebrovascular pathology, and antemortem brain imaging. The aim of this study was to correlate antemortem brain magnetic resonance imaging (MRI) volumes with postmortem brain pathology (both Alzheimer-related and cerebrovascular) in a community-derived cohort from the Framingham Heart Study. Participants (n=59) from the Framingham Heart Study were included if they were enrolled in the brain autopsy program and underwent antemortem clinical evaluation, neuropsychological testing, and brain MRI. Cortical neurofibrillary tangle pathology correlated with lower total cerebral brain (ß±SE=-0.04±0.01, P=0.004) and hippocampal volumes (ß±SE=-0.03±0.02, P=0.044) and larger temporal horns (log-transformed, ß±SE=0.05±0.01, P=0.001). Similar findings were seen between total/cortical neuritic plaques and total cerebral brain and temporal horn volume. White matter hyperintensities (also log-transformed) were best predicted by the presence of deep nuclei microinfarcts (ß±SE=0.53±0.21, P=0.016), whereas hippocampal volume was significantly decreased in the presence of hippocampal sclerosis (ß±SE=-1.23±0.30, P<0.001). This study showed that volumetric MRI measures correlated with postmortem Alzheimer-related and cerebrovascular neuropathology in this community-derived cohort, confirming that these MRI measures are important antemortem surrogates for these dementia-related pathologies.

Interrater reliability of the new criteria for behavioral variant frontotemporal dementia.

OBJECTIVE: To evaluate the interrater reliability of the new International Behavioural Variant FTD Criteria Consortium (FTDC) criteria for behavioral variant frontotemporal dementia (bvFTD). METHODS: Twenty standardized clinical case modules were developed for patients with a range of neurodegenerative diagnoses, including bvFTD, primary progressive aphasia (nonfluent, semantic, and logopenic variant), Alzheimer disease, and Lewy body dementia. Eighteen blinded raters reviewed the modules and 1) rated the presence or absence of core diagnostic features for the FTDC criteria, and 2) provided an overall diagnostic rating. Interrater reliability was determined by κ statistics for multiple raters with categorical ratings. RESULTS: The mean κ value for diagnostic agreement was 0.81 for possible bvFTD and 0.82 for probable bvFTD ("almost perfect agreement"). Interrater reliability for 4 of the 6 core features had "substantial" agreement (behavioral disinhibition, perseverative/compulsive, sympathy/empathy, hyperorality; κ = 0.61-0.80), whereas 2 had "moderate" agreement (apathy/inertia, neuropsychological; κ = 0.41-0.6). Clinician years of experience did not significantly influence rater accuracy. CONCLUSIONS: The FTDC criteria show promise for improving the diagnostic accuracy and reliability of clinicians and researchers. As disease-altering therapies are developed, accurate differential diagnosis between bvFTD and other neurodegenerative diseases will become increasingly important.

Extrapyramidal signs by dementia severity in Alzheimer disease and dementia with Lewy bodies.

Alzheimer disease (AD) and dementia with Lewy bodies (DLB) are common etiologies of dementia with overlapping clinical features. Our objective was to determine which extrapyramidal signs (EPSs) are most helpful in identifying DLB. We analyzed data from the National Alzheimer's Coordinating Center, including demographics, Unified Parkinson's Disease Rating Scale (UPDRS) scores, Mini-Mental State Examination (MMSE) scores, and clinical diagnosis. The subjects were divided into 3 groups: AD, DLB, or Lewy body variant (LBV). The UPDRS motor scores were totaled and analyzed within and across the MMSE strata using regression techniques. Further, we divided UPDRS subscores into 9 EPSs, dichotomized as either present or absent. Logistic regression analysis was used to compare each of the EPS in the AD and Lewy body (DLB+LBV) groups. DLB subjects (n=130) were more likely to be male individuals, younger, and have higher MMSE scores (P<0.001) compared with that in AD (n=1826) or LBV (n=105) subjects. Differences were found for total UPDRS score and number of EPSs (P<0.001), after controlling for age, sex, and MMSE. Logistic regression models demonstrated that masked facies best differentiated AD from Lewy body (odds ratio=6.5, P<0.001, 95% confidence interval, 3.8-11.1). If these findings are neuropathologically validated, then the presence of specific EPS may help clinicians better differentiate AD and DLB.

Cytokines disrupt intracellular patterns of Parkinson's disease-associated proteins alpha-synuclein, tau and ubiquitin in cultured glial cells.

The purpose of this study was to determine the effects of specific proinflammatory cytokines interleukin-6 (Il-6), interleukin-1beta (Il-1beta), interferon-gamma (IFN), and tumor necrosis factor-alpha (TNFalpha), on content and distribution of alpha-synuclein (alpha-synuclein), tau and ubiquitin in human derived cultured glial cells. Exposure paradigms mimicked acute (2 h), intermediate (18 h) and prolonged time frames (96 h); consisting of single or repeated low doses (10 ng/ml) or high doses (50 ng/ml), consistent with either mild or serious systemic infectious/inflammatory responses. Images of intracellular protein content and distribution were reconstructed from emission patterns generated by fluorescence deconvolution microscopy. Minor alterations were seen in protein content with IFN; Il-1beta decreased alpha-synuclein and tau at 18 and 96 h; TNFalpha inversely reduced alpha-synuclein and increased ubiquitin content. Combinations of Il-1beta and IFN produced a robust increase of alpha-synuclein and tau at 2 h. Consecutive low doses of Il-6 produced only minor increases in alpha-synuclein and ubiquitin after 4 h, whereas a single high dose resulted in major increases for all three proteins over the first 18 h. Protein localization patterns were distinctly different and were altered dependent upon cytokine treatment. A high dose exposure (2 x 50 ng/ml) with Il-6 and IFN demonstrated that protein increases and dispersals could be sustained and that the normal perinuclear tau and peripheral alpha-synuclein patterns were disrupted. These results support the postulate that specific cytokines affect temporal protein changes with concomitant pattern disruptions, possibly reflecting a mechanism of cell dysfunction in Parkinson's degeneration.